CRT zonder atriale lead: tweeledig CRT-DX-systeem non-inferieur aan klassieke drie-leads CRT-D

Background: The role of atrial pacing support is unclear in cardiac resynchronization therapy-defibrillator (CRT-D) patients without sinus node dysfunction.Methods: We conducted a randomized, parallel-group, non-inferiority trial to evaluate whether a two-lead CRT-DX system capable of atrial sensing (but no pacing) via a floating dipole on the right ventricular lead is not inferior to a three-lead CRT-D with conventional atrial lead. Between October 17, 2018, and March 5, 2024, 636 patients (68 ± 10 years old, 28.6% females) with standard CRT-D indication, optimized medical therapy, and resting sinus rate ≥45 beats/min were randomized 1:1 to CRT-DX (VDD 35 beats/min) or CRT-D (DDD 50 beats/min) at 23 Italian sites. A centralized block randomization procedure stratified by site was used, with patients and primary outcome assessors blinded to treatment assignment. The primary endpoint was a 1-year composite of all-cause mortality, cardiovascular hospitalization, and lead-related complica